1. Field of the Invention
The present invention relates to ergonomic devices for vehicle seats and more particularly to belt-type ergonomic devices.
2. Related Art
Vehicle seats typically include one or more ergonomic device, such as a lumbar support. Belt-type ergonomic devices are a common type of vehicle seat ergonomic device. The belt-type ergonomic device generally includes an adjustable belt or strap. The belt supports the vehicle seat occupant and is adjusted to vary the effective length or stiffness of the support.
Previously, belt-type ergonomic devices adjusted only on one side or included complex devices for bi-lateral adjustment. When the belt or strap is adjusted only on one side, the belt does not provide uniform support to the seat occupant. Non-uniform support often leads to distress or discomfort of the seat occupant after a period of time.
Furthermore, in the particular art of supporting the lumbar spine, there is a need for spinal relief. That is, the bony vertebrae of the spine become uncomfortable if direct pressure is applied to them by a lumbar support pressure surface. It is preferable to apply lumbar supporting pressure bilaterally adjacent to the spinal column, while maintaining a vertical recess or channel to accommodate the vertebrae.
In addition to providing uniform, bi-lateral support, a belt-type ergonomic device must also be crashworthy. Vehicle seats must meet government and industry standards of crashworthiness, and although an ergonomic device must be simple to use, cost effective, and easy to assemble, the ergonomic device must not decrease the overall crashworthiness of the vehicle seat. In all instances, the ergonomic device must be designed to maintain or improve the overall crashworthiness of the vehicle seat.
Finally, the belt-type ergonomic device must be designed with its manufacture in mind. Economy, efficiency and speed of assembly are always a concern in manufacturing industries, particularly the automobile industry. There is a constant need for reducing costs of component assembly and packaging for shipments of those components between manufacturers and assemblers of them.
Therefore, there is a continuing need in the art for a simple, cost-effective device for bi-lateral adjustment of a belt-type ergonomic device. There is a need in the art for a belt-type ergonomic device that provides spinal relief and is also crashworthy. Finally, there is a need for reduced costs and increased efficiency in the assembly of ergonomic devices.